What is triangle count? If pokemon from Sword and Shield model has a different triangle count but looks exactly the same as in Sun and Moon model, is it the same model?
You’re probably thinking about a 3D mesh. Some people refer to it as a model, but the word “model” often carries other connotations with it. I said I wouldn’t write anything more about Pokemon in specific, but this is an opportunity to segue into a more general look at how 3D graphics work in general and I think that’s a worthwhile topic to cover, so let’s take a dive down that rabbit hole. We’ll start with the mesh. A 3D mesh usually looks something like this:
As you can see, this is a polygonal mesh for bulbasaur. It is comprised of a bunch of points in space called vertices that are connected to each other in varying degrees. These connections between vertices are called “edges”. Typically, edges are grouped into threes and called “triangles”, each of which represents a solid surface on the model. The general complexity of the 3D mesh is proportional to the number of triangles it is comprised of. As a point of reference, Spider-Man PS4′s various spider-suit meshes had between 80,000 and 150,000 triangles.
However, you may have gathered that this mesh isn’t the entirety of the 3D model. It’s is just the shape of the thing. You also need to know what it looks like, what parts are colored what, and so on. This means you need to add a texture map to it in order to see what parts of it look like what. A texture map is a 2D image that has certain established points “mapped” to vertices on the 3D mesh. It ends up looking something like this:
You can see how specific parts of the Texture Map in the upper left get applied to corresponding parts on the 3D Mesh - there’s a section of the Texture Map for the tail, the face, the body, the paws, etc. We can also have multiple texture maps for a single 3D mesh. Here’s another example - each of these guns uses the same 3D mesh but a different texture map.
Are these models the same? Well… they all use the same 3D mesh, but clearly they have different texture maps applied, each of which required somebody to create them. Let’s hold off on judgement for a moment though, because we’re not done yet.
It describes the heights and shape of a surface that isn’t smooth. It lets us make smaller numbers of triangles look like they have a lot more details without needing to break them up into significantly higher numbers of triangles. The two examples here are both using the same 3D mesh, but with different normal maps applied. Are these two models the same? Well, they both use the same 3D mesh and texture map, but not the same normal map. But let’s hold off for a moment again because we’re still not done.
There’s also specular maps…
… and ambient occlusion maps…
… all of which can be different while keeping things like the 3D mesh and/or texture map the exact same, especially between one game and another. This also is only discussing elements of the model and doesn’t go into things like the rig (animation skeleton) or the individual animations that can also be different.
There’s clearly a lot of work that goes into the creation of a 3D model. We obviously have to build the mesh but we also have to build things like the texture map, the normal map, the specular map, the ambient occlusion map, and any specific shaders. For a game like Pokemon, in some cases you might keep the old mesh and the texture map, but create brand new normal maps, specular maps, ambient occlusion maps, and shaders. So you end up with something that looks like this:
Clearly the specularity is different - look at how more shiny and reflective the Let’s Go version is. The shaders are also different - note how much better defined the lines are around the model in gen 8. The mesh itself is probably the same. The texture map might be the same. The normal map is definitely different - you can clearly see how the shadowing is different between the two, especially around the chin and lower torso. So is this a new model or an old one? My answer is “yes” - some parts of it are new and some are not. But is it the exact same model? They are clearly not the exact same model - there has definitely been work done between the two. Claiming otherwise would be foolish.
The FANTa Project is currently on hiatus while I am crunching at work too busy.
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